Storage tank for volatile gases and liquids



April 21, 1931. .1. H. WIGGINS STORAGE TANK FOR VOLATILE GASES ANDLIQUIDS Filed Feb. 15. 1928 3 Sheets-Sheet l April 21, 1931. J. H.WIGGINS STORAGE TANK FOR VOLATILE GASES AND LIQUIDS Filed Feb. 15, 19283 Sheets-Sheet 2 v. .2 FllllllIIllllidlwlnlillnlnzllI.

hvmavroe: JOHN J-/- W/66/N6.

April 21 J. H. WlGGINS STORAGE TANK FOR VOLATILE GASES AND LIQUIDS FiledFeb. 15, 1928 3 Sheets-Sheet 3 Patented Apr. 21, 1931 UNITED STATES mms; wreems, 011mm omen STQBAGE TANK FOB VOLATHIE GASES AND LIQUIDSApplicationflled February 15, 1928. Serial Ho. 254,518.

. This invention relates to apparatus of the kind that are used forstoring volatile liquids and gases.

One object of my invention is to provide a a combined liquid storagetank. and 'gasolene vapor recovery apparatus'which are so constructedand arranged that while it is possible for gases to escape freely fromthe :storage tank to the vapor reoovery'apparatus under 1 certainconditions, it is impossiblefor the ases to esca e from the tank or bewithrawn from t e tank at such a rate as to create a vacuumin the tankthat will injure the tank or cause it to collapse. Another object is toprovide a combined storage tank and gasolene vaporrecovery apparatuswhich are so constructed and arran d that dry gases from the gas holderof t evapor recovery apparatus will be ad mitted to the tankautomatically under certain conditions.

Another object is to provide a storage tank of the general typedescribed in my prior U. S. Patent No. 1,645,313, dated October 11,

1927, that is equipped with a vacuum relief valve which is of suchdesign that the downward movement of the roof of the tank is utilized toproduce power which causes said valve to open and admit air or gas tothe in- $9 terior of the tank, either to prevent a vacuum from beingcreated in the tank, or to. increase the internal pressure of the tank.7

And still another object of my invention is to provide an apparatus forstoring volatile liquids and recovering the gases and vapors evolvedfrom same, that is safe, of rugged construction, and of such des' thatthe automatically operating valves 0 same do not require constantinspection, adjustment or repair to insure their remaining in anoperative condition. Other objects and desirable features of myinvention will be hereinafter pointed out.

Figure 1 of the drawings is a vertical transverse sectional view,illustrating one kind of storage tank that can be used in an ap ra-' tusembodying my invention, said view eing taken on the line 11 of Figure 2.I

Figure 2 is a to plan view of said tank. Figure 3 is an en argedhorizontal sectional view of the volume'control pressure relief valve,taken on the line 3+3 of Figure 4.

Figure 4 is an enlarged vertical sectional view of the volume-controlressur' relief valve, taken on the line 44: 0? Figure 2.

Figure 5 is an enlarged vertical sectional view of one of the ieldingsustaining devices on the roof, ta en on the line 5-5. of Figure 2.

Figure 6 is a diagrammatic view, illustrating the tank shown in Figure1, combined with a gwolene. vapor recovery apparatus.

Figure 7 is a fragmentary top plan view of a storage tank equipped witha volume-control pressure relief valve and a vacuum valve of slightlydifferent construction and arrangement from those used in the tankillustrated in Figure 1; and.

Figures 8 and 9 are vertical sectional views,

taken on the lines 88 and 9-9 of Figure 7 r In the accompanying drawingswhich illustrate the preferred form of my invention, A designates astorage tank ofthe general type disclosed in my prior patent previouslyreferred to, which is provided with a roof or top B that is capable offlexing upwardly and downwardly a limited distance from a horizontalplane, so as to increase and decrease the vapor. space of the tankwithout liability of setting up injurious strains in the roof. When theinternal pressure of the tank becomes greater than the weight of theroof, due to the expansion of the gases or vapors in the tank, the roofwill flex upwardly, and thus increase the volume of the vapor space inthe tank. Thereafter, when the internal pressure of the tank diminishes,the roof will flex downwardly, thus automatically decreasin the volumeof the gas or vapor space. ormally, the roof occupies a' downwardlydeflected position, as shown in full lines in Figure 1, and at suchtimes the roofis sustained by a stationary supporting structure insideof the tank comprising radially-disposed members C. When the internalpressure of the tank becomes greater than the weight of the roof, due tothe expansion of the gases and vapors in the tank, the roof B flexesupwardly more or less, as indicated by broken lines in Figure 1.

equipped with an inlet valve or vacuum valve designated as an entiretyby the reference character E in Figure 1, that opens automatically andadmits air or to the tank when the roof reaches a certain position initsdownward movement.

As previously'stated, two of the objects of my present invention are asfollows:

(1) To combine a storage tank of the gen-' eral type referred to with agasolene vapor recovery apparatus in such a way that the gases or'vaporscan pass from the tank tosaid recovery apparatus without-liability ofthe tank being injured or damaged, due to the gases or vapors beingwithdrawn from same at such a rate as to create a vacuum in the tank;and v (2) To combine such a tank with such an apparatus in such a waythat dry gases, or gases stripped of gasolene vapors, can pass.

automatically from the gas holder of the recovery apparatus into thetank under certain conditions, as, for example, when the internalpressure of the tank drops below a certain approximate degree, or whenthe in-' ternal pressure of the tank becomess'diminlslllfigd, due towithdrawing liquid from the ta Accordingly, in Figure 6 of the drawingsI have illustrated the tank A combined with a gasolene vapor recoveryapparatus which comprises a device F of any suitable type or kind forstrip ing gasolene vapors or for removing gaso ene vapors from the gaseswhich escape from the tank A when the volurine-control ressure reliefvalve D opens, a gas holder 6 combined with the stripping device F insuch a way that the dry gases will pass from the device F into the gasholder G, and a return pipe H leading from the gas holder G to thevacuum valve E for admitting dry gases to the tank A when said vacuumvalve opens. It is immaterial, so far as my broad idea is concerned,what type or kind of inlet valve or vacuum valve E is used to admit asesto the tank at a certain point in the ownward movement of the roof,except that the movement of the roof mustoperate this intake valve, butI prefer to equip the tank with an inlet valve or vacuum valve of suchdesign that the downward movement of the roof is used to produce powerwhich causes said valve to open. Accordingly, when such a valve is used,it is preferable to equip the roof B with a'plurality of yieldingsustaining devices 1- that project downwardly from the underside of theroof and co-operate with the supporting structure to hold the rootspaced slightly away fromsaid supporting structure when wardly,,belowits normal position, towards the supporting structure 0 whenever apartial .vacuum exists.v in the tank, as, for example,

when liquid is being withdrawn from the tank.

' This-slight downward movement of the root from its normal position,represented in full open the vacuum lines in Figure 1 towards thesupporting.

is immaterial,- but they are herein illustrated as consisting ofspring-pressed devices, each of which comprises a, plunger 1 (see Figure5), that projects upwardly through a tubular housing 2 connected to thetop side of the roof and combined with an expansion spring 3 thatisinterpos'ed between a collar I or abutmentd'on the plun er and acooperating abutment 5 that is justably mounted in the housing 3.The'abutment 5 is screwed into an internally screw-threaded portion atthe upper end or the housing 3 and isattached. to a sleeve 5 thatisaccessible from the upper end of the housing after the cap 3 of thehousin has been removed, said sleeve 5" being a apted tobe turned orrotated so as to raise or lower the spring abut ment 5, and thus 'varythe tension of the spring 3.- In the operation of fabricating the roof Bor joining the plates that constitute the roof, said plates aresustained by the supporting structure Cl After the plates have beenconnected together so' as to form an imperforate diaphragm which isconnected at its peripheral edge to the side wall of the tank thesprings 3 that are associated with the plungers 1 are set at such atension that said plungers will exert suflicient force against thesupporting structure C to raise the roof ofi said supporting structure,as shown in Fi re 1. The vacuum valve or inlet valve E lscomposed of agas-tight housing 6 attached to the top side of the roof, an annularvalve seat 7 inside of said housing that surrounds an inlet opening 8formed in the portion of the roof B that constitutes the bottom of saidhousing, and a horizontally- .disposed valve element 9 arranged to acton ies e of the liquid sealed type. The T return pipe B that leads fromthe gas holder 7 G ofthe vapor recovery ap aratus communicates with theinterior the housing 6, thus causing the valve element 9 to be heldtightly against its seat 7 by the pressure .0 the dry gases inthe returnpi H. However, whenever the roof B moves ownfrom the position shown infull lines in Wardly beyond a certain point, for examkple,

ure 1, the stem of the valve element 9 is brought into engagement withthe member C of the supporting structure with which it aligns, therebycausing said valve element to remain at rest while the roof 3 continuesto move downwardly, thus efiecting the unseatin of said-valve element.As soon as said v ve element unseats or 0 ns, dry gas will pass into thetank from t e return pipeH, and thus raise the internal pressure of thetank, or supply sufiicient gas to the tank to 'prevent a-destructivevacuum from being created in the'tank; As soon as the roof starts torise or move fnormal automatically, and thereafter remains in itsulpwardly back to its osition, the va ve element 9 closes closedcondition until the roof again moves downwardly to such a point as toeffect the unseating of said valve element. With an inlet valve orvacuum valve of the construction above described a very slight partial'vacuum inside ofthe tank A causes said valve to open automatically,notwithstanding the fact that there is considerable pressure in thehousing 6 which is exerted on the valve element 9 in a direction ten tohold said valve element againstits seat, cue to the fact that a forcetending to unseat or open the valve is exerted on the roof of the tankin a direction tending to draw said roof and the valve seat 7 downwardlyaway from the valve element 9 which is held at rest by the supportistructure C against which the stem 10 of t e valve bears. While I haveherein illustrated the vacuum valve or inlet valve E as being heldseated by a gaseous medium under. pressure, I wish it to be understoodthat any other suitable means can be used to hold said valve seated, solong as the valve is mounted or combined with the roof of the tank insuch a way that the downward moveis attached to the top side of the roofB of the tank in alignment with a gas outlet 14 in said roof, theinterior of the housing 13 being connected by a pipe 15 with thegasolene vapor stripping device F of the recovery apparatus. The valveelement 11 is riggure 4, andcomprises a valve.

idly connected to a stem 16 that passes upwardly through a guide 17 onthe valve seat member, and a s ring 18 is inte d between the guide 1 anda stop 19 on the valve stem 16, so as to'exert upward pressure on thevalve element 11 tendin to move it towards its seat. If desired, t evalveelement 1.1 and the seat with which it co-operates can beconstructed, in such a way as to form a liquid sealed valve, the valveelement herein illustrated being rovided with an annular trough 11 thatolds a sealing liquid in which the lower edge portion of the valve seatmember 12 is normally submerged. The valve stem 16 has pivotallyconnected to same a depending link 20 which is provided adjacent itslower end with across piece 21 that is arranged beneath one of themembers C of the supporting structure inside of the tank.

"During the upward movement of the roof from its depressed towards itselevated posi- I tion, the cross piece 21 .comesinto engagement withthe'supportin structure 0, thereby arresting the upwar movement of thevalve element 11 and causing it to remain at rest while the roof and thevalve seat member 12 carried by the roof continue to move upwardly,which action of course results in unseating the valve element 11. Assoon as said valve element has been unseated or opened, the gases orvapors escape from the vapor space of the tank A through the pipe 15into the stripping device F, thereby relieving the internal pressure ofthe tank and preventing the roof from being subjected to destructive orinjurious strains, the roof moving downwardly" to its normal position asthe volume of the gases in the tank diminishes, and final- 1 coming torest in the position shown in ll lines in Figure 1, when the internalpressure of the tank becomes less than the weight of the roof.

In Figure 7, 8 and 9 of the drawings I have illustrated 'another kind ofstorage tank that .can be used with an apparatus of the kind illustratedin Figure 6, which storage tank is equipped with a volume-controlpressure relief valve and a vacuum. or inlet valve mounted on the roof Bof the tank adjacent the side wall of the tank. The flexing of the roofof the upward and downward movement of'the roof is used to produce powerthat causes said valves to open, but the mechanism that is actuated bythe movement of the roof is located adjacent the center of the roof andis connected by means of rods or other suitable actuating devices withlevers or similar elements associated with the'valves. In the tank shownin Figures 7 to 9 the vacuum valve or inlet valve is so constructed andarranged that it will admit air or dry gases to the tank, even thoughthe tank is under pressure. In other words, the roof B of the tank isnormally held in a position with its central porinlet valve to open. Itwill thus beseen that it is immaterial, so far as my invention isconcerned, whether a artlal vacuum or a positive pressure exists in. theta at the time the inlet valve opens. In Figures-7, 8' and 9 thereference character D designates as an entirety the volume-controlpressure relief valve, and the reference character E. designates as anentirety the vacuumvalve or inlet valve. lhe valve D comprises a valveelement 11 that co-operates with 'a valve seat 12, and said valve seatand valve element are arranged inside of a gas-tight-housing 13 which isconnected by means of a pipe 15 with the gasolene vapor stripping deviceF of the recovery apparatus, said housing 13 communicating with a gasoutlet" 1a in the roof B of the tank, and the spring-actuated stem 16 ofthe valve element 11 being arranged in contact with the horizontal armof a hell crank lever 22 whose vertical arm is connected by means of arod 23 or other suitable device with an actuating mechanism,-hereinafter described, that is arranged adjacent the central portion ofthe root B of the'tank. 'The vacuum valve or inlet valve E (shown inFigure 9) also comprises a valve elementt that co-operates with a seatZ, and said valve element and valve'seat are arranged inside of ahousing 9 on the roof of the ta that communicates with an inlet opening8in said root, the stein 10 of the valve element being arranged incontact with the horizontal arm of a bell crank lever 24 whose verticalarm is connected by means of a rod or other suitable device 25 with theactuating mechanism previously referred to located adjacent the centerof the roof of the tank. This actuating. mechanism is herein illustratedas comprising two bell crank levers 26 and 27 pivotally mounted in anysuitable manner on the upper side of the roof B of the tank. Thevertical arm of the bell crank lever 26 is fastened to the rod 23associated with the volume-control pressure relief valve D, and thehorizontal arm of said bell cra lever is pivotally connected to adepending link 20 provided'with a cross iece 21, which is adapted toengage one o the supporting members C on the inside of the tank duringthe upward movement of theroof, and thus cause the bell crank lever26 torock in a direction to cause the bell crank lever 22 to unseat or openthe valve element 11 of the volume-control pressure relief valve D. Thebell crank lever 27 that is associatedwith the inlet valve orvacuumvalve E has its vertical arm connected to the rod 25, as shown inFigure 9. Attached to the horiownwardly' 'tion on the i 5-;

neonate aontal arm of the bell crank lever 27 is a device l0 that isarranged in alignment with one of the supportin members C. Consequent,when the rec B moves downwardly vbeyon a certain approximate position,the device 10?, with the bell crank lever 27, will come in contact withthe supporting member C, and if the roof thereafter continues to movedownwardly, the bell cr lever 27 will be rocked in a direction to causethe bell crank lever 24 to open or unseat the element 9 of the inletvalve E. If desired, the roof B of the tankcan be equipped with a ventvalve 28, shown in Figure 8, that opens automatically and establishescounication between the atmosphere and the vapor space of the tank whenthe volume of the gases or ee. This vent valve 28 is =1 a Bar in generalvalve E, used in the tank illustrated in Figure 1, and the stem 16 ofsaid valve is pivotally connected to a link 20 which is provided at itslower end with a cross piece 21 arranged can be adjustably combined withsaid li so as to permit said cross pieces to be ar= ranged indifierent-positions to cause the volume-control pressure relief valve Dand'the vent valve 28 to open at difierent times or at diderent pointsin the upward movement of. the roof B, the means herein illustrated forefiecting the adjuent ofsaid cross pieces consisting of a series ofholes 29 in each of the links adapted to receive a removable pin 30 thatholds the cross piece in-a certain posie or other actuating devices 23and 25 that are, associated with the valves D and E, respectively,extend radially from the actuating mechanism at the center of the roofof the tankover supporting devices 31, and if desired, said rods can beprovided with turn-buckles 32 that can be adjusted so as to accuratelycontrol the opening and closing of the vacuum-control pressure reliefvalve and the inlet valve.

es'ign to the volume-control pressure relief 1 vapors in the tankreaches a dangerous deice In an apparatusof the construction abovedescribed, there is no danger of the gases be- Y ing withdrawn from thestorage tank into the tank is used to control the opening and closing ofthe volume-control pressure relief valve which establishes and cuts oilcommunication between the vapor space of the till storage tank and thestripping'device F of the vapor recovery apparatus. In other words, theescape of the gases from the storage tank While I have hereinillustrated the vacuum valve or inlet valve as forming part of anapparatus in which the unseating or opening of said valve causes dryases to be admitted to the store e tank, I wis it to be understood thatsaid va ve is not restricted to use in an apparatus of the articulartype herein illustrated, as one eature of my present invention consistsof a storage tank provided with a flexible roof and equipped with a vacuum valve or inlet valve which is so constructed and arranged that thedownward'movement of the roof is utilized to produce power that causessaid valve to open. An apparatus of the construction herein describedenables volatile liquids to be stored with safety, the apparatus is orvery rugged construction, and

' it is equipped with automatically-operating valves that do not requireconstant inspection or repair tokeep them in an operative condition,thevalves being held seated or closed by pressure which is high enoughto eliminate the possibility of their opening accidentally, and beingunseated or moved into their open position by a positive pressureproduced by the up and down movement of the root.

Having thus described my invention, what I claim as new and desire tosecure by Letters Patent is:

1. An apparatus for the purpose described, comprising a storage tank forliquid pro vided with a roof that is capable of flexing upwardly anddownwardly to increase or decrease the volume of the vapor space of thev tank under certain conditions, means operated by the movement of theroof forpermitting. gases to escape from the tank when the roof reachesa certain approximate position during its upward movement, a pipeattached to the roof and leading from a supply of gas, an inletvalveheld seated by the gas in said supply pipe for admitting gas to thetank, and means operated by the movement of the roof for causing saidinlet valve to open in the event the roof moves downwardly beyond acertain approximate position. 2. An apparatus of the kind described,comprising a storage tank adapted to receive vol atile liquids andprovided with a roof that is capable of flexing downwardly from a certamapproximate normal position, a gas supply pipe connected with the roofand leading from a supply of gas under pressure, an inlet valve on theroof that is normally held seated by the pressure in said supply pipe,and means whereby the downward movement of the roof from its approximatenormal position causes said inlet valve to open automatically and admitgas-to the tank from said supply pipe.

3. A tank for storing volatile liquids and gases provided with aflexible roof that is adapted to flex upwardly and downwardly relativelyto an intermediate horizontal plane so as to increase and decrease thevapor space of the tank, an inlet valve that controls an opening throughwhich a gaseous medium is admitted to the tank, a stationary structurearranged inside of the tank under the roof, yielding devices on the roofadapted to (best with said structure to normally hold the roof spacedaway from said strucunder certain conditions, an inlet valve in the roofthat is normally held seated, and a device that co-operates with saidsupporting structure during the downward movement of the roof towardssaid supporting structure to cause said valve to open.

5. In a stora e tank of the type that is provided with a exible roofwhichis adapted to flex upwardly and downwardly relatively to anintermediate horizontal plane to vary the volume of the vapor space ofthe tank, a stationaryroof supporting structure arranged inside of thetank on the underside of the roof, a valve mounted on the roof, meansfor holding said valve seated, and a means adapted to co-act with saidstructure and rendered operative by the flexing of theroof, forpositively unseating said valve.

6. In a storage tank ofthe t pe provided with a roof that is adapted toflex upwardly and downwardly to vary the volume of the vapor space ofthe tank, an inlet valve on the roof, a seat for said valve arrangedunderneath the same, and a part on the valve that co-operates with ameans on the inside of the tank for arresting the movement of the valverelatively to its seat so as to cause the valve to open during thedownward movement of the roof.

7. A storage tank provided with a roof that is capable of flexingupwardly and downwardly relatively" to an intermediate horizontal planeto increase or decrease the volume of the vapor space of the tank underseat for said valve carried by the roof and arranged above the valve,and a means ren- I dered operative by the upward flexing of the roof forexerting a direct pull on said valve so as to open the same. I

9. In a storage tank of the type that is provided'with a roof which isadapted to flex upwardl and downwardly relatively to an interme 'atehorizontal plane to vary the volume of the vapor space of the tank, anoutlet valve for venting the tank or reducing the internal pressure ofsame, a seat for said valve carried by the roof and adapted to movewithzsame, a means for holding said valve seated, arranged on theexterior of the tank, and a means rendered operative by the upwardflexing of the roof for opening said valve.

10. In a storage tank of the type-that is provided with a roof which isadapted to flex upwardl f and downwardly relatively to an intermediatehorizontal plane to va 4 the volume of the vapor space of the't anoutlet valve for venting the tank or reducing the internal pressure'ofsame, a seat for sai valve arranged above the valve and carried by theroof, a

ring for holding said valve seated, arrange above the valve, and a meansfor unseating the valve that is adapted to co-act with a part on the'inside of the tank durin the upward flexing of the roof.

11. a storage tank of the type that is provided with a roof which isadapted to flex.

upwardl and downwardly relatively to an interine 'ate horizontal planeto vary the volume of the vapor space of the tank, an outlet valve forventing the tank "or reducing the internal pressure of same, an annularseat for said valve arranged above the valve and carried by the roof, ameans that normally exertspressure on said valve in a direction tendingto hold it against said seat, and a means for exerting a direct pull onsaid valve in a direction to 0 en the same during the upward movement 0theroof. 12. In a storage tank of the type that is provided with a roofwhich is adapted to flex, upwardly and downwardly relatively to anintermediate horizontal plane to vary the volume of the vapor space ofthe tank, an outlet valve for venting the tank or reducing the internalpressure of same, a seat for said valve arranged above the valve andadapted to move with the roof, and a means for exerting a direct pullonsaid valve to open the same during the upward movement of the roof,comprising a device suspended from the valve and provided with a partthat adapted to engage. a stationary means loing the internal pressureof same, a seat for said valve arranged above the valve and carried bythe roof, a stem projecting upwardly from the top side 'ofthe valve, aguide for said stem arranged above the valve, a means that co -acts withsaid stem to hold the valve seated, and a means that is renderedoperative by the upward flexing of the roof for openin the valve. Y

14. a storage tank of the type that is provided with a roof which isadapted to flex upwardl and downwardly relatively to an interme atehorizontal plane to vary the volume of the vapor space} of the tank, anoutlet valve for venting or reducing the internal pressure of the tank,a seat for said valve arranged above the valve and adapted :to move withthe roof, a means for said valve located outside of the' as ace of thetank, and a device suspen ed om the valve and adapted to co-act witha-stav tionary part inside of the tank to unseat the valve during theupward movement of the roof. S

15. Ina storageftank provided witha roofwhich is a a ted'to flexupwardly and downwardly re atively to an intermediate horizontal planeto vary the volume of the vapor sp'aceof the tank,

an outlet valve for venting the tank or reducin the internal pressure ofsame a seat for said valve arranged above the valve and adapted to movewith the roof, a means arranged on theoutsi'de of the gas space of isthe e that is the tank for holding said valve seated, and

a depending part on said valve rovided with an adjustable means that isadapted to co-act with a means inside of thee-tank for causing saidvalve to move away from its seat during the upward movement of the roof.a

16. In a storage tank of the type that is provided with a roof which isadapted to ex upwardly and downwardly relatively to an intermediatehorizontal plane to vary the volume of the vapor space of the tank, anoutlet valve for venting the or reducing the internal pressureof'same,'an

and adapted to move with the roof, a stem 'prOJecting upwardly from thetop side of seat for said valve arranged above the valve said valve, aguide through which said stem passes, a spring mounted on said stembetween said guide and an abutment on the stem for normally holding thevalve seated, a depending part pivotally connected to the underside ofthe valve, and a member on said depending part that is adapted tocooperate with a means inside of the tank for causing said valve toseparate from its seat during the upward movement of the roof.

JOHN H. WIGGINS.

